CHAPTER ONE
1.0   INTRODUCTION
The theme of this research is based on the perception of farmers of the effect of climate change on farm produce. It has been logically argued that climate change may positively and negatively affect  the growth of crop in agricultural system.
In some broken down analysis, climate is a sole determinant for the success of  farm produce and its harvest as well. Emphasis are hereby made below under some given headings.
1.1BACKGROUND TO THE STUDY
According to Kolbert., (2006) climate encompasses the  temperatures, humidity, atmospheric pressure, winds, rainfall, atmospheric particle count and numerous other meteorological elements in a given region over long periods of time, as opposed to  the term weather, which refers to current activity of these same elements.
The climate of a location is affected by its latitude, terrain, altitude, persistent ice or snow cover, as well as nearby oceans and their currents.
Climates can be classified using parameters such temperature and rainfall to define specific climate types. (Seiz, 2007)     
According to Haeberli, (2008) from Montana State University, climate change is any long term significant change in the expected patterns of average weather of a specific region (or, more relevantly to contemporary socio-political concerns, of the earth as a whole) over an appropriately significant period of time.
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Susanne, and Veizer (2008) revealed that climate change reflects abnormal variations to the expected climate  within the earth’s atmosphere and subsequent effects on other parts of the earth, such as in the ice caps over  durations ranging from decades to million of years.
Reports revealed by the inter-governmental panel on climate change (IPCC 2007) stated that  climate change in the research of a  great many factors including the dynamic processes of the earth itself, external forces including variation in sunlight intensity, and more recently by human activities, which might in future be deliberate  geo-engineering. External factors that can shape climate are often called climate forcing and include such processes as variations in solar radiation, deviations in the Earths orbit and the level of greenhouse gas concentrations.
There have been so many variations on carbondioxide(Co2) during the last 50 million years. The increased carbondioxide level are thought to exacerbate the heating effects of the greenhouse effect by reading the re-radiation of heat from the sun and, therefore, increasing the temperature contained in the atmosphere.
As the ability of the atmosphere to capture and recycle energy emitted by the Earth’s surface is essential to a stable climate, this heightened temperature may introduce a de-stabilizing influence and potentially affect global weather patterns and eventually, long-term climate change.
(Source: Buckley, and Wallace, 2008)
Framers efforts on yielding mass harvest and encouraging large plantation may be seriously terminated and hampered from the perception of climate change. Where alternative instruments are not introduced to counteract the factors militating against favourable climate on farm produce this may lay a set back on agricultural input and output by our farmers.
It obvioused that climate change had contributed towards initiating basic subsistence farming system order than the mechanized farming product for large market of farm produce.
For example, a region where climate change had hampered the possibility of regular actual rainfall variably, water system irrigation can be applied to artificially supply wet contents on crop growth and improving regular harvest.
Farmers in Nigeria today are faced with variable challenges on climate change making the agricultural sector prone to difficulties in enhancing crop production as a result of weak alternative facilities, equipments and scientific instruments to improve the range of farming.
Dr Daniel (2008) from the University of Maiduguri revealed findings that climate change plays a significant role in agriculture by setting up limits for crop production. The main climatic elements in agriculture are temperature, moisture, sunlight, wind and evaporation. Most crops     are sensitive to episodes of high temperature. High temperatures between 45oc and 55oc that occur for at least 30 minutes directly, damage crop leaves in most environments, and lower temperatures between 35-40oc can be damaging if they persist longer.    
Awosika, and Ajayi, (2002) opined that vulnerability of crops to  damage by high temperatures varies with developmental stage thus, high temperatures during reproductive development are particularly injurious.  For example, to maize at tussling, to soybean at flowering and to wheat at grain filling.`